The present invention relates to embodiments of an apparatus for shielding the interior of a brake actuator from debris and for centering the push rod in a brake actuator chamber. Typically, a shield operates as a barrier to block entry of contaminants that might otherwise pass from outside an actuator housing, through a gap between a pushrod outer circumference and an opening in an actuator wall and into an interior of the actuator housing. In such an arrangement, the shield commonly has an inner diameter surrounding the articulating pushrod at the very location at which side loading of the pushrod occurs. For most rigid shields, shield inner diameters have been accepted as load bearing interfaces. In such a construction, if the inner diameter of a shield is compromised by side loading, the shield may no longer operate effectively. In addition, if the return spring is not centered in the actuator housing, it will skew the push rod in the housing, causing excessive wear on the diaphragm and chamber body. Therefore, there is a need for an improved shield for a brake actuator and centering device for the pushrod of the brake actuator.